Television



F. M. ROBB TELEVI S I ON April 21, 1931.

Filed May 22, 1929 9 7n INVEN QE. 9 .fi-M. Q 'ATToezEY.

Patented Apr. 21, 1931 FRANK MORSE ROBIB, F IBELLEVILLE, ONTARIO, CANADA TELEVISION Application filed May 22, 1929. Serial No. 365,051.

in regard to the size of the image and to make use of every bit of light available so as to produce a much brighter image and therefore capable of considerable enlargement by lenses; to reduce the dimensions of the scanning disc required to transmit a fair sized image by omitting the customary spaced holes in scanningdiscs and replacing these by an arrangement of slots applied in a particular manner in the operation thereof; and to limit the space required for apparatus used in television and lightenrthe same, and thereby obviate the necessity of operating the rotated parts at a comparatively low speed, which is essential in large wheels and discs well known in this art; to emphasize the details in the transmission of the images and give forth a much more pleasant effect. In the drawings, Figure 1 is a perspectlve view showing in an equipment for television a photographing apparatus including scanning discs, photo-electric cell and operatmg motor.

Figure 2 is a plan view of the rear disc of the two shown in Figure 1.

Figure 8 is a plan view of the front disc. Like numerals of reference indicate corresponding parts in the various figures I In television it is of course well known and common practice to use perforated discs for scanning purposes. These discs usually rotate at a fairly good speed and distribute a spot of light over a screen. 7

There are many ways of arranging the perforations and this part of the equipment in television has been developed considerably by those interested in the art, also there have been slotted discs used in overlapping arrangement, but in this invention the discs are slotted, but they are concentric, and it is this concentric setting of the discs and the slots therein that is accountable for the. particular feature of the invention, that is to say, without increasing the size of the discs a considerable area may be covered with light, or the size of the photographing image can be effectually increased.

Referring to the drawings, the two discs, indicated by the numerals 15 and 16 are arranged between the lenses 17 and 18, the lens 18- being the photographic lens in front of the'fore disc 16, the lens 17 being the concentrating lens behind the rear disc 15 and in front of the photo-electric cell 19.

The aligning of the'lenses and the photoelectric cell through the discs 16 and 17 is in a path clear of any other part of the apparatus, and the convolute slot 20 is'always in this path during rotation, also each radial slot in the rear disc 15 extending inwardly from adjacent to the edge in a radial direction registers with the convolute slot, thus embracing the whole arm occupied by the image.

It has been found desirable by those experimenting and practicing in this art, for one disc to travel at a different speed than the other disc, therefore the disc15 travels at a high speed,compared to the disc 16, and this is accomplished by driving the shaft 23 directfrom the electric motor 22, and the sleeve shaft 24 encircling the shaft 23 from the friction wheel25 in engagement with the friction disc 26, said friction wheel 25 being connected from the. shaft 23 by the flexible shaft 27, and said disc 15 being fixedly mounted on the sleeve shaft 24, while said disc- 16 is fixedly mounted on the direct driven shaft 23.

The friction wheel 25 is mounted in the bearing 28 forming part of the bracket 29, radially secured to the motor stand 30.

It will be thus seen that in this particular equipment the image is transmitted through the lens 18 by means of the distribution of the'light through the slot-ted discs, this light is conveyed to the photo-electric cell through the lens 17 and it is the movement and spread of this light in conformance with the image to be transmitted that creates the necessary impulses which may be suitably amplified and delivered to the receiving end. 5 What I claim is 1. In television, discs individually mounted from a common center and driven at se lected and different speeds and having respectively radial slots in the one disc extending inwardly to the extent of the depth of a continuous convolute slot in the other disc extending inwardly from the outer field for a chosen distance, said slots forming registering scanning apertures and cooperating with a lens directed through the upper rotating section of the combined discs and a photo electric cell tlierebehind.

2. In television, an outer disc having a scanning aperture describing a convolute curve partially around the center, an inner disc having a plurality of radially and inwardly extending scanning apertures cooperating with the aforesaid scanning aperture, a shaft mounting for said outer disc journalled in suitable bearings and driven, a sleeve shaft mounted on the said shaft, and carrying said inner disc, a gear mechanism connecting said shafts for driving said sleeve shaft at a different speed in relation to said driven shaft, a lens directed to said outer disc and a photo electric cell set behind said inner disc.

'3. In television, an outer disc having a scanning aperture describing a convolute curve partially around the center, an inner disc having a plurality of radially and inwardly extending scanning apertures coopcrating with the aforesaid scanning apertures, a shaft mount-ing for said outer disc 'journalled in suitable bearings and driven,

a sleeve shaft mounted on the said shaft, and carrying said inner disc, a friction member mounted on said sleeve shaft, a friction roller engaging said friction member and mounted 011 a shaft suitably journalled, a flexible shaft connecting said driven shaft to said roller shaft, a lens directed to said outer disc and a photo electric cell set behind said inner disc. 50 Signed at Montreal, Canada, this 28th day of March, 1929.

FRANK MORSE ROBB. 

